Is a lightweight velomobile legally capable of 50mph feasible

[DogDipstick]

Can your share some photos of your 60 mph bike? Please?

Which one? I have built three. All broke 60mph. some stronger than bicycle parts, but mostly bicycle parts. Working on the fourth. Working on the fifth too. They will be cromotor or LR big block bikes, ironhorses, with Marzochi and Risse, hammersmiths, and good brks ( magurs).

My true-DWlink Ironhorse bicycle ( is the one that cracked again, 50K miles and six years as an ebike) ... the... , Super73, the Eleek bomber.

Here is one. ... and ... hasnt happened to this bike.. but... ironically, this chassis is notorious for cracking the neck. Super73 has replaced thousands of frames after the neck broke. My white bike? I beat on it. I got thread about its build. On here... its got a couple thousand watt hours on it. I try to build at least 2kWh bikes.. no fun if not. My white bike has full write ups here. the others dont. no one cares what I built lol. I'll post a bike here, spent a year working on it... with zero comment sand so after a while... so I quit. I do post them to my DIY ebike facbook groups though since i got a good reputation there as a builder.

Im sorry I dont have any pictures of the Eleek. I do have a vid of it at 150mph on its 273 on the stand ballooning a tire. Lol. That had magura brakes and a brnd new World rally Cup RS boxxer... god what a fork. Shimano tensioners and good chainrings. all the bike parts were high end.

ok. Well a 750wh pack might be fun.. but not " as much fun"... 2kWh if more funner betterer greater than etc.


Chalo: The " neck " of a bicycle ( the image you get when you type that into an "internet search engine") is the part the fork attaches to. This is true ( read: not false for both MC and bicycles. Sure it might not be traditional nomenclature ( seatstay, stem, chainstay) but is well accepted and common vernacular when discussing two and three wheeled vehicles steered by the er uhm.. stem.. neck.

Type "bicycle neck " into Google and you will see about a thousand images about what I speak of. also referenced on the wiki page under " FRAME" .. as shown in the snippet I provide. I understand this might not be common vernacular wherst you are from, but I assure you it is common in the area I am from.

If you say " Motorcycle neck" or " bicycle neck" from where I live, the people know right away what part of the MC or bicycle you are speaking of. It is the part that the fork tube is bolted to. The frontmost part of the frame... the part that hold the steering bearing(s) and their races.

bicycle neck - Google Search

 

[The Toecutter]

I'll post a bike here, spent a year working on it... with zero comment sand so after a while... so I quit. I do post them to my DIY ebike facbook groups though since i got a good reputation there as a builder.

I've noticed that putting links to build threads in signatures accompanied by brief descriptions of the projects increases traffic to them, if only because you might say something interesting and totally unrelated to your builds in a topic elsewhere that intrigues the reader regarding your unknown-to-them build/ride experiences and they decide to take a look for some further context. Having a link readily available for them to peruse instead of them having to spend 10+ minutes searching for it themselves makes a big difference in the amount of potential interest generated.

60 mph on an ebike is no joke. I for one, am interested in having a look at your build threads. I spent about 5 minutes of searching on this forum and couldn't find any of them.

 

[Chalo]

If you say " Motorcycle neck" or " bicycle neck" from where I live, the people know right away what part of the MC or bicycle you are speaking of. It is the part that the fork tube is bolted to.

The only variation of that I've heard is from clueless old goats who call a handlebar stem a "gooseneck". The same kind of dudes who refer to cranks as "paddles". Oh, and I guess there was a BMX parts outfit like 45 years ago called Pro Neck. Maybe it was founded by clueless young goats, now old.

In terms of neck analogues, it seems like it would be equally valid to call a fork steer tube or a frame head tube a neck. Maybe I should start calling stems "snouts" to become more compatible with folks who call seatposts "stems".

 

[DogDipstick]

Yeah well I think it a HAZ problem. .. issue... I get two, three years on a repair Im happy.. I'll do it again. Keeps on breaking farther down the top tube, underneathe, the part of the ( tube) beam loading in tension, not compression, ... I keep on buttressing. The tubes are 7005 hydroformed and double butted to begin with. I should probally jsut make a copy in steel if i love it so much. I have gone over my options with some structural professionals and they told me to weld it again. As opposed to rivets, or gusset plates, or some other kind of mechanical reinforcement like a steel/ alu composite structure ( teel plates bolted here or there) taking the forces of the load.

 

[scianiac]

I'll post a bike here, spent a year working on it... with zero comment sand so after a while... so I quit.

Well I want to see more about your builds, I'm not even sure I've seen the thread on the white bike, didn't know there was one but I've looked very closely at the pictures you posted of it in places like the torque arm thread. I like the way you build things. But I get it, I always plan to take pictures as I build things and post a thread then I forget and get lazy and I think well maybe I'll just wait until it's done then it's never like completely done because I just keep tweaking things forever.

Hey eventually half the bike will be buttress and it will stabilize lol. I can recommend you go for an LR bike next, they are a difference challenge than a hub motor bike with different pros and cons to take advantage of and account for.

 

[Zambam]

Which one? I have built three. All broke 60mph. some stronger than bicycle parts, but mostly bicycle parts. Working on the fourth. Working on the fifth too. ................

bicycle neck - Google Search

Looks like no expenses spared nice builds. What are bicycle frames built to as for top speed? Did you beef up the frames? Don't know if "tank slapper" can happen on a bicycle. I had one on a motorcycle and it was scary! I didn't fight it, let the oscillation die down. Didn't crash.

 

[BalorNG]

My opinion that it is absolutely technically feasible, but not legally feasible.
It will have to be registered as a e-motorcycle, not even a moped, with appropriate parts that will kill your 'pedalable' speed due to much higher weight and rolling resistance.
Also, you'll have to forget about it being 'crash worthy', but than motorcycles don't have even that (but have leathers that saves them in a slide, yet are not exactly great for pedalling in hot weather!)

I think that a more or less typical e-bike componentry equipped velo ('legal' 250w motor with some tweaks to double/triple the watts) with hidden very small, but very powerful e-board motor that is geared to be most efficient at 50mph which will be used only on empty-ish, good roads well outside of cities (a touring velo) is your best bet, untill you'll get caught by the cops which, depending on country and county, may take a long while or never.

 

[n00b]

I just watched the Aging wheels YouTube video on the Twike 3 (a 1998 model). Yes, he says it is terrifying to drive.

Well Twike has a new model now called the Twike 5 which weighs 600 kg rather than the 240kg to 350 kg listed for the Twike 3.

Not sure how much better the Twike 5 will be, but apparently it is new unlike the Twike 3 that was first made 29 years ago (I.e.1995).

That certainly isn't light.

 

[Speedgeezer]

Its is possible but not quite practical.
My HPV FS26 @ 51"/128cm wheelbase begins to be a handful over 40 MPH on panic moves.
Wider tires & rims help significantly, I run 2.0 width front, 2.15" width rear all on 36mm wide rims.
As speeds rise straight line stability is improved with longer wheelbase.
With a MAC 10T capable of 60V 40 Amps the trike peaked at 36 MPH pulling 24A, about 1400 watts. The FS26 has poor aero.
Normally I set the peak to 30A but wanted to see where the limits were.

Tires are light and not designed to impact broken pavement at speed; the impacts stress squares with velocity. Good suspension is a must. At higher speeds above 30 MPH the front suspension tuning becomes crucial.

180mm Brake rotors and ducting air is useful if you ride in hills. This is no place for bargain brakes.

Wide ratio gearing will be desired. While it is possible to use a double chainring on a mid drive the chain slack takeup on a long cage derailleur won't come close to what would be needed. There are a dozen clever ways to get around those limits it just adds cost and weight.

 

[The Toecutter]

It will have to be registered as a e-motorcycle, not even a moped, with appropriate parts that will kill your 'pedalable' speed due to much higher weight and rolling resistance.

When pedaling with the motor disabled, I've found that Mitas MC2 16x2.25" tires on lightweight 16x1.5" DOT rims did not increase rolling resistance much over 20" bicycle wheels with Schwalbe Marathon Plus 20x1.75" tires on them, but now my wheels/tires are appropriate for motorcycle speeds. It doesn't feel any harder to pedal on flat ground once I'm up to speed compared to the bicycle wheels/Marathon Plus, although I do notice the added rotating mass when accelerating with the EV drive system disabled, especially when pedaling up steep hills.

Every component selected is part of a balancing act when trying to make such a vehicle both pedalable and capable of sustaining high cruising speed. I'm thinking I can have my trike converted to AWD, with all of the mechanicals appropriate for cruising 60 mph on a state highway, including roll cage and body, while weighing under 120 lbs or thereabouts. Should I get it to that point, it will still be very pedalable, where if I shut the motors off, rolling averages faster than what I can maintain on a normal upright bicycle will still be possible. I expect to have about twice the aero drag as my Milan SL velomobile, which would still be very slippery.

But using the motor(s), it should be dynamically safe operating as a sports car even at top speed.

Where I live, as long as I have a way to switch between (1) pedal-only mode, (2) 750W/28 mph with PAS, and (3) "offroad mode" with no speed/power restrictions, I can pass as "street legal" everywhere I ride it. Except it's a track toy of a microcar pretending to be an e-bike.

In rural areas on state highways, I liked to cruise around 45-50 mph before I disassembled it for upgrades.

 

[The Toecutter]

Its is possible but not quite practical.
My HPV FS26 @ 51"/128cm wheelbase begins to be a handful over 40 MPH on panic moves.
Wider tires & rims help significantly, I run 2.0 width front, 2.15" width rear all on 36mm wide rims.
As speeds rise straight line stability is improved with longer wheelbase.
With a MAC 10T capable of 60V 40 Amps the trike peaked at 36 MPH pulling 24A, about 1400 watts. The FS26 has poor aero.
Normally I set the peak to 30A but wanted to see where the limits were.

Tires are light and not designed to impact broken pavement at speed; the impacts stress squares with velocity. Good suspension is a must. At higher speeds above 30 MPH the front suspension tuning becomes crucial.

180mm Brake rotors and ducting air is useful if you ride in hills. This is no place for bargain brakes.

Wide ratio gearing will be desired. While it is possible to use a double chainring on a mid drive the chain slack takeup on a long cage derailleur won't come close to what would be needed. There are a dozen clever ways to get around those limits it just adds cost and weight.

What is the front track width of your HPV FS26?

I've thought of buying an HPV FS, but I need for it to be able to handle more than 40 mph. Maybe a Steintrikes Mad Max would be a better choice.

My KMX can handle panic moves above 40 mph, but I need to do some custom fabrication work to make spindles and axles that are mechanically rugged enough for surviving bad roads at that speed. For comparison, I have a 38.5" front track, a 43.5" wheelbase, and gas shocks suspending all 3 wheels. The seat is placed as far forward as the frame allows, to where my center of gravity is maybe 5" behind the axle line drawn by the front wheels. My wheelbase isn't nearly as long as yours, but the wide front track makes it very maneuverable and tip-resistant, and in hard cornering, it skids like a car instead of trying to tip over. I can do donuts in the middle of intersections with this thing. It feels plenty stable careening downhill at 60 mph, and I imagine a longer wheelbase would only improve things regarding stability. With a motor in all 3 wheels, hydraulic disc brakes up front coupled with all-wheel regen should be sufficient for panic stopping it from speed.

 

[n00b]

Most velomobiles are under 60kg, and a few are classed as mopeds, such as the Northern Light 630, which although capable of 50mph, can only legally do 28mpg. To get any vehicle legally capable of 50mph, the next weight bracket seems to be over 250kg where I can only find one which is still a velomobile which is the Twike3 which is only loosely a velomobile as by its own definition the pedal assists the motor, rather than motor assisting the pedal power, so compared to the Northern Light 630 where 200W is enough to sustain 30mph without any electric assistance, for the Twike3 power, 200W only provides 20% of what is required.

There are lot of regulations to make a 15mph velomobile Ebike legally capable of 28mph, but there seems to be very little additional regulation to make it legally capable of speeds up to 70mph - the main thing being the design and construction which covers the chassis, sub-frame, body parts, wheels, axles and suspension to assess the ability to withstand the forces and vibrations imposed during acceleration, braking and cornering when fully laden. Do the extra stresses on a velomobile of increasing the speed from 28mph to 50+mph mean lightweight cycle components cannot be used and must be replaced by much heavier motorbike/car components? So for example would it be possible to alter the Northern Light 630 or the Begorett Angelina (which also has a moped/Super Pedelec version) to be more sturdy, to make it legally a motor trike/quad bike somewhere around 100kg, or does it require a major redesign to be safe at higher speeds?

I would say it might could be done, but it will not be pleasureable or safe.

 

[The Toecutter]

I would say it might could be done, but it will not be pleasureable or safe.

More pleasurable to operate than most conventional vehicles, and safer than a bicycle or motorcycle, by my experience. My coroplast-bodied velomobile made from a KMX trike with full suspension was like operating a little British sports car, except even more maneuverable and lighter in mass, nevermind faster to accelerate.

 

[Speedgeezer]

What is the front track width of your HPV FS26?

I've thought of buying an HPV FS, but I need for it to be able to handle more than 40 mph. Maybe a Steintrikes Mad Max would be a better choice.

My KMX can handle panic moves above 40 mph, but I need to do some custom fabrication work to make spindles and axles that are mechanically rugged enough for surviving bad roads at that speed. For comparison, I have a 38.5" front track, a 43.5" wheelbase, and gas shocks suspending all 3 wheels. The seat is placed as far forward as the frame allows, to where my center of gravity is maybe 5" behind the axle line drawn by the front wheels. My wheelbase isn't nearly as long as yours, but the wide front track makes it very maneuverable and tip-resistant, and in hard cornering, it skids like a car instead of trying to tip over. I can do donuts in the middle of intersections with this thing. It feels plenty stable careening downhill at 60 mph, and I imagine a longer wheelbase would only improve things regarding stability. With a motor in all 3 wheels, hydraulic disc brakes up front coupled with all-wheel regen should be sufficient for panic stopping it from speed.

The FS26 Front track Center to Center is 31.2".
Front suspension is a bit limited in travel and not as well damped. Anti-rollbar is a great asset.
10.7 Lb Wolf battery under the boom to keep weigh low and forward (Geared Hub).
20x2 Big Apples on 36mm wide rims, and 26x2.15 Big Ben on back, 3 way adjustable 165mm airshock.
Shimano M785 Hydro clampers with Ice Tech pads, 165 mm rotors.

Handling is pretty good but with fluid dampers would be more confident at higher speeds. They use a friction damper with spring & elastomer so as speed increases the damper simply doesn't work very well. Hydraulic would make a difference here. The 60mm tube frame is rock solid and seating position with Bodylink seat is ideal for drifting by leaning over.
Hard turns on ultra grippy tires are a blast almost too much fun.

My other trike is a Steintrike Wild One. Its a 3x20 and has same tires/rim widths and a BBS02 with 52V 14AH battery.
180mm Rotors with TRP Spike Mech brakes (fabulous), front 800Lb DVM Spring shocks, rear 3-way adjustable shock.
Shorter wheelbase don't recall it but that has an impact for sure.
Front springs are preloaded with about 50Lb per side, stiff. Above about 20 MPH braking is skitterish in part due to the geometry and the lack of an anti-rollbar. The difference is at 30 MPH downhill on smooth pavement threshold braking is controllable but the brake dive erodes confidence compared to the Scorpion. However really rough pavement doesn't take an confidence away on the Steintrike like it does on the Scorpion.

 

[bikestickmonkey]

Most velomobiles are under 60kg, and a few are classed as mopeds, such as the Northern Light 630, which although capable of 50mph, can only legally do 28mpg. To get any vehicle legally capable of 50mph, the next weight bracket seems to be over 250kg where I can only find one which is still a velomobile which is the Twike3 which is only loosely a velomobile as by its own definition the pedal assists the motor, rather than motor assisting the pedal power, so compared to the Northern Light 630 where 200W is enough to sustain 30mph without any electric assistance, for the Twike3 power, 200W only provides 20% of what is required.

There are lot of regulations to make a 15mph velomobile Ebike legally capable of 28mph, but there seems to be very little additional regulation to make it legally capable of speeds up to 70mph - the main thing being the design and construction which covers the chassis, sub-frame, body parts, wheels, axles and suspension to assess the ability to withstand the forces and vibrations imposed during acceleration, braking and cornering when fully laden. Do the extra stresses on a velomobile of increasing the speed from 28mph to 50+mph mean lightweight cycle components cannot be used and must be replaced by much heavier motorbike/car components? So for example would it be possible to alter the Northern Light 630 or the Begorett Angelina (which also has a moped/Super Pedelec version) to be more sturdy, to make it legally a motor trike/quad bike somewhere around 100kg, or does it require a major redesign to be safe at higher speeds?

Most velomobiles are super light, like the Northern Light 630, which can do 50mph but is legally limited to 28mph. To hit 50mph legally, you'd need something heavier like the Twike3. Upping the speed means you’d need sturdier parts, swapping out lightweight cycle components for beefier motorbike/car ones.

 

[The Toecutter]

Most velomobiles are super light, like the Northern Light 630, which can do 50mph but is legally limited to 28mph. To hit 50mph legally, you'd need something heavier like the Twike3. Upping the speed means you’d need sturdier parts, swapping out lightweight cycle components for beefier motorbike/car ones.

Adding a second person to the vehicle also greatly increases the sturdiness required of the mechanical components, and therefore greatly increases the mass of the vehicle.

The Northern Lights 360 may indeed be mechanically rugged enough for street use to its full capabilities, nevermind merely being stable at such a speed(unlike the Twike), even if the law in the UK doesn't allow for that. I'd like to see someone try to test that. From a mechanical reliability perspective, thee NL360 may prove safe at 50 mph, regardless of what the law says is safe.

The Twike is way too heavy for one person to pedal at an appreciable speed. It is fully dependent on the electric motor, even if it may not be fully propelled by it. And its chassis geometry and body shape are both ill-suited to 40+ mph. Pedalability is a great benchmark for gauging the vehicle's efficiency. If you can't pedal it to at least bicycle speeds on a disabled battery, then you're wasting energy pushing air out of the way or too much mass up a hill in anything where the goal is inexpensive, high-speed, long-distance individual transportation for all seasons. Anything with a CdA over 0.15 m^2 and a mass over 80 kg is totally extraneous and unnecessary for such a vehicle if it has seating for one, even if it's built for 70 mph.

My own build has been very stable and easily controlled at 45+ mph, even if the brakes and some of the mechanical bits at the time weren't intended by their manufacturers for that usage case. It weighed all of 91 lbs. Unlike the NL360, its crashworthiness was closer to the non-existent end of the spectrum with the bicycles, scooters, and motorcycles. Which is why I like my Milan SL: it has crumple zones and a built-in safety cell, and I look forward to motorizing it. So does the NL360 have crumple zones and a safety cell.

My gripe with the NL360 is it isn't nearly as aerodynamically slippery as most commercially-available velomobiles, and is losing out on performance potential as a result. The Milan will probably hold 70+ mph with 2 kW fed to the motor, and still weigh little enough to pedal to faster-than-bicycle speeds on a disabled motor.

There's nothing stopping a vehicle with stouter mechanicals and slightly more mass from getting similar slipperiness to a well-designed velomobile, but it is also possible to take the bicycle drivetrain out and give it AWD and car-like horsepower for not much money. I think a sub-80 kg one-seater built like an Electrathon car, perhaps 2-3x the drag of my Milan, with AWD and 100+ peak kW via hubmotors, with a dynamically stable cruising speed of around 100-120 mph, is possible, and it would get to top speed from a stop faster than many supercars can hit 60.

Something like the NL360 but with better suspension, wheels/tires, brakes, more ground clearance, and greatly more slippery aerodynamics, could make for a great one-person highway-capable commuter, that if mass produced in sufficient quantity, could be priced like a moped or scooter. But with anything over 20+ kW of applied power, it would have supercar-like performance. Said vehicle would allow the rider comfort in inclement weather, and due to aerodynamics, get long range for a small battery(5 kWh or less would be plenty). Imagine your commuter only requiring $20/year of electricity to charge in order to ride 20,000 km/year. Solar panels of sufficient area to give you 30+ miles range per day also would be inexpensive and useful for such a vehicle, while still fitting on it.

 

[Chalo]

I think a sub-80 kg one-seater built like an Electrathon car, perhaps 2-3x the drag of my Milan, with AWD and 100+ peak kW via hubmotors, with a dynamically stable cruising speed of around 100-120 mph, is possible, and it would get to top speed from a stop faster than many supercars can hit 60.

Not by twisting sub-20mm flatted axles, it won't. At least not for long. So you're not only reinventing the velomobile, you're also reinventing the hub motor.

'Bout damn time, if it happens.

 

[Gruesome]

Pick any combination of the following:

1) Lack of mass production capability among anyone willing and able to make them. This limits possible market scope. Hand building such a vehicle will make it cost in the $10,000 range, like a velomobile. Not many people will buy at that price. Maybe double or triple digit sales per year. In order to have mass appeal, the cost has to get into the mid-$X,XXX range, to compete in purchase cost with a decent running used car.

2) Legal issues. Without a license/insurance/registration, there are very few places on Earth where this vehicle would be technically legal to operate. Add in the cost of these things and taxes, you negate much of the cost advantage and appeal of such a vehicle over a car.

3) Liability issues. Some governments will want to treat this vehicle like a car, and once enough accidents/fatalities occur, the manufacturer will be held liable. In accidents with a car, the occupants of these vehicles will lose every time.

If I were rich, I'd be building such vehicles for the commercial market right now. I think such an option has potential, and will only become more relevant and important as natural resources dwindle, fiat currency increasingly becomes debased, real wages decline, energy becomes more expensive/scarce, ect. But I'm not rich, and barley have time to progress on my own personal projects.

You also forget the Velion, a 28 mph electric-assist velomobile:

Home | Velion

Once they get the next gen out that can accept front hub motors, I've had thoughts of buying one, reinforcing any weak areas of the chassis, upgrading to hydraulic disc brakes, and converting it into a < 150 kg 35+ kW micro sports car with AWD so that I can commit all kinds of vehicular jackassery with it.

A few years after WWII there were a lot of lightweight vehicles in Europe. Scooters were very popular. A few of the German airplane manufacturers got into small vehicles: Messerschmitt 'Kabinenroller' , BMW Isetta. Once people had more money and could afford real cars, the demand disappeared.

Regarding 'bicycle neck' referring to the junction of fork and steering head: unlikely. Google shows me handlebar stem pictures:

 

[Gruesome]

Yeah well I think it a HAZ problem. .. issue... I get two, three years on a repair Im happy.. I'll do it again. Keeps on breaking farther down the top tube, underneathe, the part of the ( tube) beam loading in tension, not compression, ... I keep on buttressing. [...]

HAZ as in 'heat affected zone'? So, a welding mistake?

 

[DogDipstick]

HAZ as in 'heat affected zone'? So, a welding mistake?

Yes.

 

[Mike Bounds]

A few of the German airplane manufacturers got into small vehicles: Messerschmitt 'Kabinenroller' , BMW Isetta. Once people had more money and could afford real cars, the demand disappeared.

This is a big issue in anyone bringing small vehicles to the market. I once worked somewhere where a manager was complaining how long it took him to get into work each day for a short 2 mile journey due to traffic so I suggested he cycle in, at least on fair weather days, especially since he went to the gym everyday after work. This suggestion was laughed at saying I haven't worked my way up to be a manager and have nice car to then cycle into work. This mindset needs changing so rather than thinking that if you drive a small very efficient car, or use a pedal bike, that you must be poor or need to save costs, that actually you are doing a lot for the environment by using a vehicle which both uses far less resources to produce as well as to run and of course as a consequence can be cheaper to buy and certainly cheaper to run.

Unfortunately, if a small efficient vehicle has a pedal generator where cycling to contribute is optional, this would probably be seen as a downside as to many this would also be perceived as solely something to reduced costs, whereas in reality the cycling aspect saves very little cost as even if you are reasonably fit and can sustain 200W this means in one hour of travel you will save 3-4 cents or 4-5 pence.
For me, the point of adding pedal power is that you push the design to be extremely efficient so that pedal input is meaningful as a percentage of the force required and this design is what saves running costs and makes the pedal input psychologically worth it. Even someone with a fairly modest 100W cycling output, could be contributing half the power to maintain 30mph for a small efficient vehicle and this psychological affect can mean you persist with the pedalling and try to improve which of course improves fitness and both physical and mental health. Also driving is "dead" time, so if you can exercise while driving you are either getting extra exercise or can spend less time on other exercise.

To be fair a lot of micro cars don't look great and this is being polite and the same is true for a lot of velomobiles where many have a niche look and don't look like they would be very stable going round corners. There is hope with some better looking velomobiles shown below with more thought to crash protection too, which I actually think look good as oppose to a compromise in looks compared to a car, but I think limited to 28mph they have limited appeal for replacing some car journeys (like for people with 2 cars in a household)

BEGORETT:


Northern Light Motors:

 

[The Toecutter]

For me, the point of adding pedal power is that you push the design to be extremely efficient so that pedal input is meaningful as a percentage of the force required and this design is what saves running costs and makes the pedal input psychologically worth it. Even someone with a fairly modest 100W cycling output, could be contributing half the power to maintain 30mph for a small efficient vehicle and this psychological affect can mean you persist with the pedalling and try to improve which of course improves fitness and both physical and mental health. Also driving is "dead" time, so if you can exercise while driving you are either getting extra exercise or can spend less time on other exercise.

This is exactly what I'm after, because any vehicle I make that doesn't have bicycle pedals, I still want for it to be as efficient as possible for its application. It will go faster with less horsepower as a result, with compounding cost savings for the operator in most aspects.

Take such a vehicle and give it a power to weight ratio that exceeds that of any supercar. Design it in a way that the vehicle is both reliable and inexpensive even when compared to a motorcycle. THIS is how you make such a thing sell itself, and piss off all the rich people that masturbate to their supercar collections that think such performance should be "exclusive" to them and priced accordingly, while upsetting many industry applecarts in the process by targeting a price point that a Chinese peasant might be able to afford.

 

[The Toecutter]

Not by twisting sub-20mm flatted axles, it won't. At least not for long. So you're not only reinventing the velomobile, you're also reinventing the hub motor.

'Bout damn time, if it happens.

Cotter pin axles are a thing. 12mm bicycle axles won't do for this. Added mass: < 1kg.

 

[Chalo]

HAZ as in 'heat affected zone'? So, a welding mistake?

Every weld has a heat affected zone; so no, not a mistake. A good quality uncontaminated weld using the correct filler metal can be heat treated after welding to return to near original properties, but that often doesn't happen.

 

[Gruesome]

Every weld has a heat affected zone; so no, not a mistake. A good quality uncontaminated weld using the correct filler metal can be heat treated after welding to return to near original properties, but that often doesn't happen.

I think the poster said he had a failure in the HAZ, or even repeated failures.